BACKGROUND:

Renal cell carcinoma with translocation on chromosome Xp11.2 was recognized in 2004 by the World Health Organization. That neoplasia is associated with different micro-arrangements, particularly of the TFE3 gene on the Xp11 chromosome. Prevalence of the translocation varies from 1-1.6% of all kidney tumors in the adult population.

CLINICAL CASE:

A 64-year-old woman presented with moderate left lumbar pain radiating to the ipsilateral upper quadrant two months prior to hospital admission. Computed tomography urogram identified a heterogeneous tumor at the lower pole and middle portion of the left kidney that measured 20 x 17 x 14 cm, with irregular edges and calcifications. There was bilateral perihilar lymph node enlargement adjacent to the aorta that anteriorly displaced the vena cava. Laboratory tests reported hemoglobin of 10g/dL and calcium of 9.2 mEq/dL. Open radical nephrectomy with para-aortic lymphadenectomy was performed, revealing abundant lymph nodes in the mesentery and in the contralateral renal hilum. Pathology study diagnosis was renal carcinoma with Xp11.2 translocation (immunohistochemistry positive for TFE-3), with metastasis to one lymph node. The patient is currently undergoing the fourth cycle of chemotherapy with pazopanib, with disease dissemination to the lungs, mesentery, and cervical region.

CONCLUSION:

Renal cell carcinoma with Xp11.2 translocation usually affects children and young adults. It does not cause symptoms and the kidney masses are painless. Given that the majority of cases are diagnosed at late stages, outcome is unfavorable.